Turn: Two recursive and non-recursive for fork trees

int deep  (root node) {     int s=0;     if (node)     {     s=deep (node->left) >deep (node->right)? Deep (Node->left) +1:deep (node->right) +1;     }     return s;}

The basic idea of recursion is: in order to obtain the depth of the tree, we can first seek the depth of the left and right subtree, take the larger of the two plus 1 is the depth of the tree, recursive return condition is if the node is empty, return 0

int Treedeep (Bintree BT) {2     int treedeep=0; 3     stack S; 4     stack tag; 5     Bintree p=bt; 6 while     (p!=null| | !isempty (S)) {7         while (p!=null) {8             push (S,P), 9             push (tag,0),             p=p->lchild;11         }12         if ( TOP (tag) ==1) {             deeptree=deeptree>s.length?deeptree:s.length;14             pop (S), N-             pop (tag),             p =null;17         }else{18             p=top (S),             p=p->rchild;20             Pop (tag),             push (tag,1),         }23     }24     return deeptree;25}

　　

The basic idea of non-recursive realization:

Inspired by the subsequent traversal of the binary tree thought, we thought that we could use the method of subsequent traversal to find the depth of the binary tree, replace the size of the become stack s at each output place, and the maximum stack s length after the traversal is the depth of the stack.

The algorithm performs the following steps:

(1) When the tree is not empty, the pointer p points to the root node and p is the current node pointer.

(2) Press p into the stack s, 0 presses into the stack tag, and P executes its left child.

(3) Repeat step (2) until P is empty.

(4) If the stack top element in the tag stack is 1, skip to step (6). Return from right subtree

(5) If the stack top element in the tag stack is 0, skip to step (7). Return from Zuozi

(6) Compare the depth of the treedeep with the stack, take a larger assignment to the Treedeep, stack s and stack tag out of the stack operation, p points to null, and jumps to step (8).

(7) Point p to the stack s top element of the right child, pop stack tag, and put 1 into the stack tag. (Another way, directly modify the stack tag stack at the top of the value of 1 can also)

(8) Loop (2) ~ (7) until the stack is empty and p is empty

(9) Return to Treedeep, end traversal

Turn: Two recursive and non-recursive for fork trees